JP2002040583A - Document cover of image reading device and image reading device - Google Patents

Abstract

(57) [Problem] To provide a document cover and an image reading device of an image reading device capable of pressing a thick document with a simple configuration and firmly pressing the document even during vertical scanning. A document cover for covering a document placed on a document table, and a hinge rotatably supported at one end by the document cover and rotatably supported at the other end by the document table. A member 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image reading apparatus for reading an image of an original, such as a scanner, a copying machine, or a facsimile apparatus, and more particularly to an original cover provided in these apparatuses.

[0002]

2. Description of the Related Art FIG. 5 is a schematic diagram showing the configuration of a color image reading apparatus.

[0003] P is a read document placed on the platen glass 100, and an image on the document is read by scanning the contact image sensor 101 in parallel with the platen glass 100.

As shown schematically in FIG. 6, a contact image sensor 101 includes three color LEDs 101R, 101G, and 101B, which are light sources for illuminating an original, and reflects light reflected from the original on a light receiving element of the image sensor. Rod lens array 101L and image sensor 1
01S is incorporated. The light sources of the three colors are sequentially switched and turned on, and the image sensor reads the reflected light from the document for each color to perform color separation reading.

The contact image sensor 101S is fixedly supported on a slider 102 which slides on a guide shaft 103 fixed to the apparatus main body. Also, slider 1
A belt 104 for transmitting power from a motor 105 serving as a scanning drive source is fixed to 02. By the forward / reverse rotation of the motor, the contact image sensor 101S can perform reciprocal scanning in the range of the document table glass 100.

The components of the image reading apparatus include an electrical unit 106 including a control board and a power supply in addition to the above components. These components are arranged in a cover 110 that fixedly supports the platen glass 100.

An original cover 111 for pressing an original onto the glass is provided on the original platen glass 100.
The document cover is attached to be openable and closable about a fitting portion between a concave portion 110a provided at a rear end portion and a convex portion 111a at a rear end portion of the document cover. The platen glass 1 on the inner surface of the cover
The sheet material 112a and the sponge 1
An original pressure bonding sheet 112 made of 12b is attached.

FIG. 7 is a block diagram of the read image data processing by the image reading apparatus. The image output signal read by the image sensor 101S in synchronization with the sequentially blinking LED is sent to the amplifier 121, amplified, and then converted into a digital image signal by the A / D converter 122.

The A / D converter divides the dynamic range of the image sensor (the read output difference between the pure white part and the pure black part on the original) by the number of bits, and performs gradation according to the brightness of the image on the original. Assign a number.

For example, when an A / D converter having a resolution of 8 bits is used, 256 gradation levels are set during the period from white to black, and 1 when a 10-bit A / D converter is used.
024 gradation levels.

Therefore, in an image reading apparatus using an 8-bit A / D converter, 24 bits = approximately 16.7 million colors and 10 bits in color reading using a light source of three colors of RGB.
In this case, 30 bits = approximately 1.074 billion colors can be identified.

There are several types of output modes of the image signal of the image reading apparatus, and an output mode suitable for the read image can be selected depending on the use of the read image.

When reading a text and applying the content to OCR or when reading a monochrome line drawing, a monochrome binary image is suitable, and it is obtained by turning on, for example, only G among the above RGB light sources. Image data obtained by binarizing an image signal at a certain threshold value by an image processing circuit incorporated in the gate array 123 is used.

When reading an image such as a photograph and outputting the image to a monochrome printer, the image is similarly binarized by using an image signal from a G light source and using a halftone process such as a dither method or an error diffusion method. The image data obtained is used.

When performing color image processing, multi-valued (24-bit etc.) image data is suitable.

The image signal that has passed through the image processing circuit is transmitted to an apparatus 20 such as a personal computer via an interface circuit 124.
Output to 0.

[0017]

However, in the case of the above-described prior art, the following problems have occurred.

The image scanner having the above configuration is very small and light by utilizing the features of the contact image sensor. Therefore, as shown in FIG.
In some cases, one side is down using 00 to be placed vertically, so that it can be used even in this state. Documents that can be scanned vertically are limited to sheet-shaped ones, but the document cover and the end of the device should be closed with a suction cup or the like, and the document should be pressed against glass for scanning.

On the other hand, the original cover in the configuration of the prior art is opened and closed by rotation about a fulcrum at the rear end, but this method cannot hold a thick original such as a book. Generally, the document cover slides up and down to accommodate thick documents.

However, in such an image scanner, when the hinge is configured as described above, the hinge is opened when the document is placed vertically, and the document cover is lifted from the glass so that the document cannot be pressed down. I couldn't do that.

The present invention has been made in order to solve the above-mentioned problems of the prior art, and its object is to be able to hold a thick original with a simple configuration, and to firmly hold even a vertical scanning. An object of the present invention is to provide a document cover and an image reading device of an image reading device capable of holding down a document.

[0022]

According to the present invention, there is provided a document cover for an image reading device provided on the image reading device and covering a document table on which a document is placed. A cover member for covering the original placed on the platen,
A hinge member rotatably supported at one end by the cover member and rotatably supported at the other end by being attached to the document table.

Preferably, the hinge member is rotatably supported in a region other than the end of the cover member.

[0024] It is also preferable that the cover member is provided so that a rotatable range with respect to the hinge member is regulated.

It is also preferable that a regulating portion for regulating the rotation of the cover member with respect to the hinge member is provided on at least one of the cover member and the hinge member, or a regulating member having the regulating portion is provided. It is.

[0026] It is preferable that an urging member for urging the hinge member in a direction to open the cover member is provided.

[0027] It is also preferable that an urging member is provided for urging the cover member in a direction in which the rotation of the cover member with respect to the hinge member is restricted by the restricting portion.

Preferably, the urging member is a torsion coil spring.

It is also preferable that the biasing member is a flexible metal wire or a belt-like member.

The urging member is preferably a part of the cover member or the hinge member.

The image reading apparatus is characterized in that the image reading apparatus includes the document cover of the above-described image reading apparatus and image reading means for reading image information of a document placed on a document table.

[0032]

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the dimensions of the components described in this embodiment,
The material, the shape, and the relative arrangement thereof should be appropriately changed depending on the configuration of the apparatus to which the invention is applied and various conditions, and are not intended to limit the scope of the invention to the following embodiments.

(Embodiment 1) FIGS. 1 and 2 are configuration examples of an image reading apparatus according to Embodiment 1. FIG. In FIG. 1, reference numeral P denotes a read original placed on the original platen glass 1. By scanning a contact image sensor 2 as an image reading means in parallel with the original platen glass 1, image information on the original is read. The contact image sensor 2 incorporates a light source for illuminating the original, a lens that forms reflected light from the original on a light receiving element of the image sensor, and an image sensor.

Reference numeral 11 denotes a frame which also serves as an exterior cover, in which the original platen glass 1 and the contact image sensor 2 are placed.
In addition, a rail for guiding the traveling of the contact image sensor 2, a transmission mechanism for transmitting a driving force to the contact image sensor 2, and a motor, a control board, a power source, and the like as a driving source are housed.

As shown in FIG. 2, an original cover 12 and a hinge member 13 as cover members for pressing an original onto the glass are provided on the original table glass 1.
1 and a fitting portion between the concave portion 11a provided at the rear end portion and the convex portion 13a at the rear end of the hinge member 13, and a fitting portion between the convex portion 13b at the front end of the hinge member 13 and the concave portion 12a at the rear end portion of the document cover 12. It is installed to be openable and closable with two points of the part as a fulcrum.

The rear end 12b of the document cover 12 projects beyond the fulcrum (12a / 13b) engaged with the hinge member 13 (the hinge member 13 is a region other than the end of the document cover 12 (recess 12a)). The projecting portion is regulated as a regulating portion, and the range in which the document cover 12 can rotate with respect to the hinge member 13 is regulated.

Further, a torsion coil spring 14 as an urging member is attached around the fulcrum (12a / 13b), and the document cover 12 is opened with respect to the hinge member 13 (at the rear end 12b which is an overhang portion). Regulated)
Biased in the direction. A sheet material 15a and a sponge 15b are provided on the inner surface of the cover facing the platen glass 1.
Is attached.

Further, a suction cup 16 is attached to the leading end of the document cover 12. In addition, on the exterior 11, the suction cup 16
The position opposed to is finished to a smooth surface so that the suction cup 16 can easily adhere.

The sponge 15b of the original pressing sheet 15 is
The document cover 12 is closed and the suction cup 16 has such a thickness that the suction cup 16 is slightly crushed in close contact with the exterior 11.

The operation of the present invention is as follows. When the original cover 12 is opened in the normal flat position, the original cover 12
Are fixed to the hinge member 13 by the effect of the projecting portion of the rear end 12b, so that they rotate integrally. Then, as shown in FIG. 2 (c), the opening posture is maintained when the angle exceeds 90 °.

Next, when a thick original such as a book is set and the original cover is closed, as shown in FIG.
Is bent downward by its own weight about the fulcrum between the hinge member 13 and the document, and assumes a posture covering the document.

In the case of vertical scanning, an original is placed on the original platen glass 1, the original cover 12 is closed, and the suction cup 16 is pressed from above, whereby the original comes into close contact with the exterior 11. At this time, the sponge 15b of the original pressure-bonding sheet 15 is bent, so that a reaction force is applied to the original via the sheet material 15a, and even if the original has wrinkles or curls, it is stretched and adheres to the glass.

When a sheet-shaped original is set flat, the original cover 12 is closed on the original glass 1 by its own weight. However, when the apparatus is placed vertically, the weight of the original in the direction of the platen glass 1 is not applied.
/ 13b) floats from the platen glass 1, ie,
Although the document cover 12 is easily rotated in the closing direction with respect to the hinge member 13, the open position is maintained by the action of the torsion coil spring 14. Therefore, the fulcrum (12a
/ 13b) no longer floats from the platen glass 1,
We can hold manuscript well. Therefore, a clear image can be read.

In the present embodiment, the rear end 12b of the document cover 12 has a fulcrum (12a / 13)
Although it protrudes more rearward than b), it may be engaged with the hinge member 13 at the rear end 12b. Further, the rear end 12b of the document cover 12 serves as a regulating portion, which regulates the rotation of the document cover 12 with respect to the hinge member 13, but the regulating portion is provided on at least one of the document cover 12 and the hinge member 13. Or another regulating member may be provided.

(Embodiment 2) FIG. 3 shows Embodiment 2
It is shown. In the present embodiment, the first embodiment
An example is shown in which a spring wire 17 as a flexible metal wire is used instead of the torsion coil spring. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

The central portion of the wire 17 is fixed to the hinge member 13 at 13c, and both ends are engaged with the hook portions 12c of the document cover 12 so as to be movable in the longitudinal direction of the wire 17. When a thick document is placed and the document cover 12 is closed, the document cover 12 rotates in the closing direction with respect to the hinge member 13 as shown in FIG. 3B. A restoring force in the opening direction acts on 13, and thus has the same effect as in the above-described embodiment.

In this embodiment, since the shape of the spring is simplified, cost reduction can be expected. Also, the wire 17
Instead of this, it is also possible to use a leaf spring as a flexible band-shaped member.

(Embodiment 3) FIG. 4 shows Embodiment 3
It is shown.

Usually, the document cover and the hinge member are made of a plastic material. Therefore, in the present embodiment, as shown in FIG. 4, a part 13d of the hinge member is formed in a thin band shape so that this part has resiliency, and one end thereof is engaged with the hook part 12d of the document cover. Thus, a function equivalent to that of the above embodiment can be provided.

The implementation of this method eliminates the need for a spring member and can further reduce costs.

Note that the spring portion in the present embodiment can be provided on the document cover side.

[0052]

As described above, according to the present invention,
A cover member for covering the document placed on the platen; and a hinge member rotatably supported at one end by the cover member and rotatably supported at the other end by being attached to the platen. Thus, a thick original can be pressed with a simple configuration.

Further, since the cover member is restricted in its rotatable range with respect to the hinge member, even when the apparatus is placed vertically, the hinge will not be opened unlike the conventional case, and the document must be pressed firmly. Can be.

Further, by providing an urging member for urging the cover member in the opening direction with respect to the hinge member, it is possible to reliably press the document without opening the hinge, particularly when the apparatus is placed vertically. Therefore, a high-quality image reading device can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an image reading apparatus according to an embodiment.

FIG. 2A is a schematic top view of a document cover, and FIGS. 2B to 2D are diagrams for explaining the operation of the document cover.

FIG. 3 is a schematic configuration diagram of an image reading apparatus according to a second embodiment.

FIG. 4 is a schematic configuration diagram of an image reading device according to a third embodiment.

FIG. 5 is a schematic configuration diagram of a conventional image reading apparatus.

FIG. 6 is a schematic diagram showing a contact image sensor.

FIG. 7 is a read image data processing block diagram.

FIG. 8 is a schematic diagram showing the image reading apparatus in a vertically placed state.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 platen glass 2 contact image sensor 11 exterior 11 a recess 12 document cover 12 a recess 12 b rear end 12 c hook portion 12 d hook portion 13 hinge member 13 a projection 13 b projection 13 c hinge fixing portion 13 d part of hinge member 14 torsion coil Spring 15 Original pressure bonding sheet 15a Sheet material 15b Sponge 16 Sucker 17 Wire

Claims (10)

[Claims] 1. A document cover of an image reading device provided on the image reading device and covering a document plate on which a document is placed, a cover member for covering the document placed on the document plate, and one end of the cover member A hinge member rotatably supported by a member and having the other end attached to the document table and rotatably supported by the document table. 2. The document cover according to claim 1, wherein the hinge member is rotatably supported in a region other than an end of the cover member. 3. The document cover according to claim 1, wherein the cover member is provided with a rotatable range regulated with respect to the hinge member. 4. A control device for controlling the rotation of the cover member with respect to the hinge member, at least one of the cover member and the hinge member, or a control member having the control unit. The document cover of the image reading apparatus according to claim 1, 2, or 3. 5. The document cover according to claim 1, further comprising an urging member for urging the hinge member in a direction to open the cover member. 6. A biasing member for biasing said cover member in a direction in which rotation of said cover member relative to said hinge member is regulated by said regulating portion.
Document cover of the image reading device according to 1. 7. The document cover according to claim 5, wherein the biasing member is a torsion coil spring. 8. A document cover according to claim 5, wherein said urging member is a flexible metal wire or a band-shaped member. 9. The apparatus according to claim 5, wherein said biasing member is a part of said cover member or said hinge member.
Or a document cover of the image reading device according to 6. 10. An image reading apparatus according to claim 1, further comprising: a document cover for reading the image information of a document placed on a document table. Image reading device.